Patent Grant
7942352
1. Field of Invention
The present invention is generally related to shredders for destroying articles, such as documents, CDs, etc. More specifically, the present invention is related to shredders including a rotatable device for moving shredded materials in a shredder.
2. Description of Related Art
During operation of a shredder, paper or other articles are fed through the input opening or throat of the shredder to be destroyed. As shown in
One problem which may develop during shredding of articles includes when shredded particles adhere to or near the cutting assembly 102 or outlet 104 of the shredder 100. Such a phenomenon of accumulated particles known as “bird nesting,” as indicated by element 120. The shredded particles may accumulate due to physical or electrostatic means, for example. Over time, bird nesting particles 120 that accumulate near outlet 104 can become lodged inside the cutting assembly 102 or outlet 104 and reduce the sheet capacity (i.e., the amount of articles to be received and shredded in the cutting assembly) of the machine. Thus, extra strain may be placed on the gears, bearings, and motor (not shown) associated with the cutting assembly, and may even damage the cutting assembly 102. It is therefore desirable to reduce bird nesting particles 120 in order to extend the life and efficiency of a shredder 100 and maintain proper operation. This problem occurs more often in cross-cutting shredders, because the small chips formed by cross-cutting are more likely to accumulate.
Additionally, after articles have been shredded and particles descend from the housing 105, a second problem may develop. As shredded particles collect inside the waste bin 103, the shredded particles tend to accumulate in a shape similar to a peak or mountain, sometimes also referred to as “crowning,” as indicated by element 130. An accumulation of crowing particles 130 is inefficient since the particles will quickly build up. The crowning particles 130 may then perhaps start pushing against the cutting assembly 102, possibly contributing to the accumulation of bird nesting particles 120. The crowning particles 130 may also falsely or prematurely trigger a bin full detection system before the waste bin 103 is completely full. User assistance may then be required to either empty the waste bin 103, remove shreds that have accumulated near the output opening or cutting assembly, or to even out the pile of particles by hand before continuing to shred. Such assistance may not only be time consuming, but also dangerous. It is therefore desirable for a shredder to have particles which accumulate evenly in the waste bin 103, particularly in shredders that utilize a bin full detection system.
Some prior art methods have attempted to develop devices to curb such problems. For example, U.S. Patent Application 2008/0041988 A1 describes a brush-off device that slides reciprocally along shafts of a cutter assembly in an axial direction. However, the prior art fails to provide a feature for cleaning an underside of the cutting assembly or outlet. Rather, the prior art functions below the shredder housing.
To prevent crowning, the prior art, such as U.S. Patent Applications 2007/029542 A1 and 2007/0295736 A1, describes shredders having containers or bins that are rocked to prevent build up of particles. U.S. Pat. No. 7,150,422 B2 provides a manual device for pressing paper downwardly in the bin. However, none of the prior art devices are designed to operate inside or with the shredder housing to clear particles caught in the cutter elements of the cutter assembly, as well as assist in preventing crowning in the bin.
One aspect of the invention provides a shredder including a bin for receiving shredded materials and a shredder housing having a shredder mechanism mounted therein. The shredder housing is provided on the bin and includes an input opening for receiving materials and an output opening for depositing shredded material into the bin. The shredder mechanism includes a motor and a cutter assembly; the motor rotates the cutter assembly about an axis to shred materials fed therein. The shredder also includes a rotatable device positioned adjacent the output opening. The rotatable device has a shaft with a plurality of fingers extending at least partially radially from the shaft. The shaft is configured to rotate about a parallel axis adjacent the axis of the cutter elements to move shredded materials adjacent the output opening.
In an embodiment, the fingers of the rotatable device extend into the cutter assembly so as to move shredded materials caught in or around the cutter assembly adjacent the output opening. In an embodiment, the fingers of the rotatable device extend at least partially into the bin to move an accumulation of shredded materials in the bin. Thus, the shredded materials adjacent the output opening could be either or both the materials in the cutter assembly or the materials in the bin.
Another aspect of the invention provides a method for moving shredded materials in a shredder. The method includes: feeding material to be shredded into an input opening in a shredder housing of the shredder, the shredder housing being provided on a bin for receiving shredded materials; and shredding the material with a shredder mechanism mounted in the shredder housing. The shredder mechanism includes a motor and a cutter assembly, and the motor rotates the cutter assembly about an axis to shred materials fed therein. The method also includes depositing the shredded material via an output opening in the shredder housing into the bin; and rotating a shaft of a rotatable device about a parallel axis that is adjacent the axis of the cutter elements. The shaft of the rotatable device has a plurality of fingers extending at least partially radially from the shaft to move shredded material adjacent the output opening. The rotatable device is positioned adjacent the output opening. In an embodiment, the fingers of the rotatable device extend into the cutter assembly so as to move shredded materials caught in or around the cutter assembly adjacent the output opening. In an embodiment, the fingers of the rotatable device extend at least partially into the bin to move an accumulation of shredded materials in the bin. Also, in an embodiment, the method includes detecting a presence of shredded materials in relation to the rotatable device and activating the rotation of the shaft of the rotatable device upon the detection of the presence of shredded materials.
Other objects, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
The described devices herein are designed to resolve or alleviate one or more of the above-noted problems found in conventional paper shredders; specifically, where particles accumulate unevenly in the waste bin, where shredded materials or paper particles become stuck to a bottom of the shredder housing and cutting assembly, and/or when bin full detection systems inaccurately detect a full bin due to accumulation or piling of shredded materials or the materials attached to the shredder housing.
Referring now more particularly to the drawings,
Shredder housing 12 also comprises an output opening 22 or outlet on a lower side 26 (or bottom side or bottom wall or underside or bin side). In an embodiment, shredder housing 12 may include a bottom receptacle 25 to receive shredder mechanism 16 therein. Bottom receptacle 25 may include output opening or outlet 22 in its lower side 26 through which shredded material is deposited into the bin 14. The bottom receptacle 25 and/or outlet 22 may reside within the opening of the bin 14 so as to direct shredded particles into the bin. Generally speaking, the shredder 10 may have any suitable construction or configuration and the illustrated embodiments provided herein are not intended to be limiting in any way.
As noted, the shredder 10 also comprises a shredder mechanism 16 in the housing 12. When articles are inserted into the at least one input opening or throat 20, they are directed toward and into shredder mechanism 16. “Shredder mechanism” is a generic structural term to denote a device that destroys articles using at least one cutter element. Destroying may be done in any particular way. Shredder mechanism 20 includes a drive system with at least one motor 23, such as an electrically powered motor, and a cutter assembly comprising a plurality of cutter elements 18. The cutter elements 18 of cutter assembly are mounted on a pair of parallel mounting shafts 17. Typically, the cutter elements will be designed for cross-cutting (i.e., for shredding the article into small chips). See, e.g., U.S. Pat. No. 6,260,780 to Kroger et al., the entirety of which is incorporated herein by reference.
The motor 23 operates using electrical power to rotatably drive the mounting shafts 17 of the shredder mechanism 16 and their corresponding cutter elements 18 through a conventional transmission (not shown) so that the cutter elements 18 shred or destroy articles fed therein, and, subsequently, deposit the shredded materials into bin 14 via the outlet 22. The shafts 17 are mounted in relation to the throat and may be provided on lateral axes A1 and A2, respectively. The shafts 17 are configured to rotate about axes A1 and A2 so as to rotate the cutter elements 18 of the cutter assembly for shredding. In an embodiment, the shredder mechanism 16 may also include a sub-frame for mounting the shafts, motor, and transmission. The drive system may have any number of motors and may include one or more transmissions. Also, the plurality of cutter elements 18 are mounted on the rotatable mounting shafts 17 in any suitable manner. For example, in an embodiment, cutter elements 18 are rotated about axes A1 and A2 in an interleaving relationship for shredded paper sheets or other articles fed therein. In an embodiment, the cutter elements 18 may be provided in a stacked relationship. The operation and construction of such a shredder mechanism 16 is well known and need not be discussed herein in detail. As such, the at least one input opening or throat 20 is configured to receive materials inserted therein to feed such materials through the shredder mechanism 16 and to deposit or eject the shredded materials through output opening or outlet 22.
The bin 14 receives shredded materials or articles from the shredder mechanism 16 of the shredder 10. The bin 14 comprises a bottom wall, four side walls, and a top, for example. Generally, the shredder housing 12 is configured to be seated above or upon the container 18. Shredder housing 12 may comprise a detachable paper shredder mechanism, as shown in
Though not shown, a power supply to the shredder may be in the form of a standard power cord with a plug on its ends that plugs into a standard AC outlet. Generally, the use of a control panel is known in the art. For example, the upper side 24 of housing 12 may also include a power switch or plurality of switches and/or switch recess or an on/off switch. Any number of switches may be provided. A switch may be moved so as to move a switch module between states (e.g., ON, OFF), for example. For example, the switch module may communicate with a controller and a motor 23 to send (or stop) transmission of electrical signals for rotating the cutter elements 18 of the shredder mechanism 16 in a shredding direction. The switch module may also communicate so as to operate the motor 23 in a reversing manner to move the cutter elements 18 in a reversing direction, such as when there is a need to clear jams, for example. Generally, the construction and operation of switches and controllers for controlling the motor are well known and any construction for these may be used. For example, a touch screen switch, membrane switch, or toggle switch are types of switches that may be used. Also, the switch may have any number of states or signals (e.g., lights, display screen) associated therewith.
As shredder 10 is used, shredded materials (e.g., paper) are deposited/directed into bin 14. As shown in
The rotatable device 30 comprises an auxiliary shaft 32 configured to rotate about a parallel, lateral axis A adjacent the axes A1 and A2 of the cutter elements 18 of the cutter assembly. In some embodiments, the rotating shaft 32 of the rotatable device 30 may be positioned below the shredder mechanism 16, as illustrated in
As shown in greater detail in
The terms “radial” or “perpendicular” when used with respect to the fingers are not to be taken as requiring a perfect or true radial or perpendicular direction. Instead, having a perpendicular or radial extent or vector sufficient to project the fingers from the shaft for performing their function is within the meanings of these terms. Likewise, the fingers need not be straight and may have curved or other shapes.
Generally, the fingers 34 comprise an elongate shape that is capable of at least partially extending into the bin 14 as well as into the shredder mechanism 16 or the cutter elements 18. In some embodiments, the fingers 34 are provided about the shaft 32 such that they extend in a number of different directions or angles. In some embodiments, the fingers may be formed or added to the shaft 32 in a helical manner. In some embodiments, the plurality of fingers 34 comprises bristles which are fixed in position on the shaft so as to rotate with the shaft. In some cases, a plurality of fingers may be referred to as bristles or a brush, and therefore the term “fingers” should not be limiting. Fingers 34 may be made from any number of resilient materials, such as elastic or rubber, for example. In some embodiments, the fingers 34 or bristles may be made from a synthetic nylon or similar material.
As shown in
In an embodiment, fins 34a may comprise additional devices or vanes 37, which may be formed during manufacture and/or provide additional stability to the rotatable device 30. Fins 34a may also be made from any number of materials. For example, fins 34a may be formed from an elastic or rubber material, or from a substantially rigid material, such as plastic. Should the fins 34a have some flexibility or resiliency, vanes 37 may assist in providing some structural stability about its length and width.
Besides assisting in moving shredded material adjacent the outlet 22, fins 34a also assist in reducing shredded materials from falling out of the outlet 22 during emptying. More specifically, the fins 34a of the rotatable device may be oriented in a closed position to substantially prevent shredded materials from being discharged from the outlet by “closing” the outlet 22 when the shredder housing 12 and bin 14 are moved out of an operative position relative to each other. When waste bins 14 or containers are typically emptied, the cutting elements 18 of shredder mechanism 16 may have shredded materials (e.g., particles of waste or trash) caught therein (e.g., which may cause bird nesting). Thus, when the bin 14 is moved, the shredder mechanism 16 may be agitated and the particles originally stuck in the cutting elements 18 may become dislodged and fall into a housing of an outer frame and/or the area surrounding the shredder 10 (e.g., the floor). Users or consumers using shredders having a pull out waste bin in particular do not expect this type of mess and difficulty when emptying the bin. In particular, users do not want waste particles falling when the bin is not in a position to catch them (i.e., when the bin 14 is not under the shredder housing 12). However, the fins 34a may address this type of annoying waste particle mess problem by preventing the shredded materials (waste) in or adjacent the shredder mechanism 16 from being discharged from the outlet 22 during a waste bin emptying process.
Specifically, the fins 34a of the rotatable device 30 may be positioned in relation to the outlet 22 such that they are in an open position or a closed position.
Also, by moving the fins 34a into a closed position in the outlet 22 as shown in
The rotation of the rotatable device 30 may be activated in any number of ways. In some embodiments, the rotation may be activated manually. For example, a switch may be provided which triggers a motor to start rotation of the rotatable device 30. In some embodiments, the rotation of the rotatable device 30 may be activated automatically. In this case, “automatically” activating rotation refers turning or rotating the shaft 32 of the device 30 at the time or detection of a predetermined event or occurrence. For example, the rotation may be associated with the activation of the shredder mechanism 16. The rotatable device 30 may also be activated to rotate concurrently with the cutter elements 18 of the cutting assembly (e.g., such as when motor 23 is used to rotate both the shredder mechanism 16 and the rotatable device 30). In some embodiments, the rotation of the rotatable device 30 is associated with a power switch for turning on the shredder 10. As an option, a positional sensor, such as a Hall sensor, may be used to detect and control the rotational position of the device 30.
In some embodiments, the rotation of the rotatable device 30 may be associated with one or more sensing devices 36 of the shredder 10, such as “bin full” sensors. The shredder 10 may comprise at least one sensor 36 to detect a presence of shredded materials in relation to the rotatable device 30, or in relation to the shredder housing 12 and/or mechanism 16. The sensor(s) 36 may be provided on the lower side 26 of the shredder housing 12 as shown in
In some embodiments, the rotatable device 30 may also be implemented in conjunction with a plurality of bin full detectors such as sensors 36 to rotate in a specific direction based on the level of shredded material detected in the waste bin 14. In such an implementation, the plurality of sensors 36 may be positioned on the lower side 26 of the shredder housing 12 so as to detect characteristics associated with the pile 28 of shredded materials. For example, the sensors 36 may assist in determining a slope of the pile 28 or its highest position of accumulation. The device 30 may then be activated to rotate in such a way so as to move the shreds from the peak of the pile 28, to either toward a front or back or left or right side(s) of the bin 14 of the shredder 10, depending on the accumulation characteristics in the bin 14. Thus, the rotatable device 30 may more efficiently distribute the shredded material inside the bin 14.
In some embodiments, such as when the shaft 32 is rotated by a separate motor, a rotary sensing device may be associated with the rotatable device 30. Such a rotary sensing device may be used to verify that the device 30 rotates to a predetermined position (e.g., a horizontal position). For example, as shown in
The rotatable device 30 is designed to alleviate both bird-nesting 120 and crowning 130 problems in shredders, as discussed with reference to
In addition, as the fingers 34 are rotated they also engage and disperse shredded materials entering or accumulating in the bin 14. Thus, the rotating device may act as a raking device, so that a pile 28 may be leveled and a more even pile may be formed in the bin 14. This allows the bin 14 to more effectively fill to capacity, as well as reduce premature bin full alerts detected by sensors, that may require user attention.
It should be noted that the position of the rotatable device 30 (or its rotating shaft 32) below the shredder mechanism 16 contributes to providing the above-noted benefits. The rotatable device 30 is able to perform two functions using a single device. Additionally, the rotatable device 30 as described herein rotates in a circular motion, rather than a reciprocal motion as provided in the prior art. This is advantageous because the rotatable device 30 is able to assist in cleaning shredded materials from the underside of the shredder mechanism 16 and/or cutting assembly, as well as near the lower side 26 of the shredder housing 12 (e.g., such as in the bin 14). Moreover, the rotating shaft design improves upon reciprocal or sliding shaft designs because it reduces the risk of device or its bristles from becoming jammed by stray particles, and possibly malfunctioning.
Also, the positioning of the fingers 34 from the surface 33 of the shaft 32 should not be limited. In some embodiments, the fingers 34 may be designed to extend from the shaft 32 in a diagonal or angled relationship with respect to axis A. The design or shape of the fingers 34 also should not be limiting. For example, the fingers or bristles may be designed in any manner such that they are able to at least partially extend into the bin as well as into the shredder mechanism 16. The fingers may have a rounded, angled, polygonal, or elongate shape. Also, the fingers 34 may be added to shaft 32 or manufactured with shaft 32 so as to form a uniform assembly. Alternatively, as previously noted, other shaped devices, such as paddles or elongated shapes, and other configurations, such as extending along or around the shaft 32, may be used and are not beyond the scope of this disclosure.
While the principles of the invention have been made clear in the illustrative embodiments set forth above, it will be apparent to those skilled in the art that various modifications may be made to the structure, arrangement, proportion, elements, materials, and components used in the practice of the invention.
It will thus be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing preferred specific embodiments have been shown and described for the purpose of illustrating the functional and structural principles of this invention and are subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1085975 | Dilg | Feb 1914 | A |
| 1706935 | Milne | Mar 1929 | A |
| 7150422 | Wang | Dec 2006 | B2 |
| 20070029542 | Yamada | Feb 2007 | A1 |
| 20070295736 | Wang | Dec 2007 | A1 |
| 20080041988 | Wang | Feb 2008 | A1 |
| 20080156914 | Huang | Jul 2008 | A1 |
| Number | Date | Country |
|---|---|---|
| 8-1027 | Jan 1996 | JP |
| 2002-239405 | Aug 2002 | JP |
| 2004-321993 | Nov 2004 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20100140383 A1 | Jun 2010 | US |
